DE2739341A1 - Multiple rinsing process for electroplating plants - using progressively cleaner water from interconnected storage tanks - Google Patents

Abstract

The workpiece is successively exposed to several rinsing liqs. e.g. four liqs. (1,2,3,4) held in four tanks (1,2,3,4). The liqs. are contaminated by progressively reducing amts. of impurities resulting from the rinsing operations and starting from the liq. (0) carries by the workpiece from a surface treatment plant. At least part of the liq. used in one rinse is fed back into the tank holding a liq. for an earlier rinsing operation. The pref. plant uses four tanks (1-4) connected by valves to a pump feeding the liqs. (1-4) successively into a spraying tank. The drain pipes from the spraying tank are fitted with a network of valves, so that e.g. after using liq. (3) is can be drained into tank (2) which contains a more contaminated liq. than tank (3). Used in continuous rinsing of e.g. electroplated workpieces, in one tank via spraying nozzles fed with successively cleaner liqs. esp. water.

Description

FROM KREISLER SCHONWALD MEYER EISHOLD FUES FROM KREISLER KELLER SELTING

PATENT LAWYERS Dr.-Ing. by Kreisler f 1973

Dr.-Ing. K. Schönwald, Cologne Dr.-Ing. Th. Meyer, Cologne Dr.-Ing. K. W. Eishold, Bad Soden Dr. J. F. Fues, Cologne Dipl.-Chem. Alek von Kreisler, Cologne Dipl.-Chem. Carola Keller, Cologne Dipl.-Ing. G. Selling, Cologne

5 COLOGNE 1 31st AUq. 1977

OEICHMANNHAUS AT THE HAUPTIAHNHOF

Friedr. Blasberg GmbH & Co KG, 565O Solingen Multiple rinsing process for surface wet treatment systems

The invention relates to a multiple rinsing process for surface wet treatment systems, in which the object to be washed in successive wash cycles from different Detergent containers with rinsing fluids are sprayed with increasingly less concentrate carryover and the draining Rinsing liquid is fed back into one of the containers, as well as a multiple rinsing system for implementation of the procedure.

In a known Mohrfachspülverfahren (DT-OS 24 Ik 082) of the type mentioned, several detergent containers, which form storage chambers for different surface treatment liquids, are arranged next to one another. The surface treatment tub, into which several galvanizing drums for the items to be treated can be lowered and rotated there, is stationary above the detergent containers. A suction cap can be moved along a rail running transversely to the detergent containers, which can optionally be inserted into each individual detergent container

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Telephone: (0221) 23 45 4t - 4 ■ Telex: 888 2307 dopa d - Telegram: Dompalcnt Cologne

can be sunk. A drain connection is connected to the intake mouthpiece. The surface wet treatment the objects are carried out by spraying that rinsing liquid in their detergent container the suction nozzle is sunk. The one dripping off the objects and the one that splashed past Liquid is collected in a tub and into that container via the drainage nozzle returned from which it was taken. This means that the concentrate is carried over to the rinsing liquid of a certain detergent container increases steadily during the wet treatment of the objects, because the rinsing liquid returned through the drain port into the detergent container is stronger is carried over or contaminated by the concentrate than that rinsing liquid that is caused by the EinsaugmundstUck has been sucked from the same detergent container. The rinsing liquids in the individual detergent containers are therefore already so heavily enriched with concentrate in a relatively short time that that they must be renewed. The known system is therefore not suitable for continuous operation.

In another known method for flushing objects (DT-AS 18 05 655) runs through the object has a pre-rinse bath and a post-rinse bath after the surface treatment has been completed. The pre-rinse has of course, a larger carry-over of concentrate than the final rinse. Both bathrooms will have valves controlled, regenerated flushing liquid supplied.

At the same time, used rinsing liquid is drained from both detergent containers. In the drainage line A conductivity meter is connected to the rinsing bath, which measures the electrical conductivity of the detergent running off the spanking

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degree determined and, depending on this, the supply of regenerated detergent to the pre-wash bath and to the Rinsing bath controls. With this method, continuous operation is possible because of the concentrate loads of the two rinsing baths can be kept relatively constant by the control system, but the system requires especially with a large number of rinsing stations, a lot of space and the use of a Immersion flushing also uses a significant amount of flushing liquid.

Finally, immersion rinsing processes are known in which the individual detergent containers are cascaded are arranged one behind the other. Each detergent container has an overflow that leads to the next Detergent container, the rinsing liquid of which has a greater degree of carryover, leads. That way will Each detergent container is continuously supplied with detergent from the respective upstream detergent container. The last flushing agent container, the flushing liquid of which has the greatest degree of carryover, can be connected to a Recyclable material processing plant to recover the concentrate rinsed off the objects or to a Be connected to the drain, during the first rinsing agent container with the lowest degree of carryover completely unloaded detergent is supplied.

The object of the invention is to provide a multi-powder Driving the aforementioned type, which is kontinuierljc h feasible, in-which the Kontratverschleppungen In the individual detergent containers during continuous operation can be maintained substantially constant.

In this case, to the different rinsing cycles are exposed in a single rinsing articles to be washed, so that a reaction between two spooling

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processes are omitted.

To solve this problem, the invention provides that with each spill cycle at least part of the draining rinse liquid is fed to a detergent container, from which flushing liquid was withdrawn during a previous flushing cycle.

The invention provides a cascading flow of the Rinsing liquid in a spray process. The rinsing liquid withdrawn from a specific detergent container is sprayed against the object and then not again that detergent container supplied from which it has been removed, but the downstream detergent container with the next higher one Degree of concentrate carry-over. The rinsing liquid, which is the last detergent container with the largest Concentrate carryover has been removed after it has been used to carry out the first rinsing process has been sprayed against the object coming out of the treatment system, then not a detergent container, but a waste processing plant in the form of an ion exchanger, evaporator, filter and the like. Or quite simply fed into a drain directed.

The inventive method offers the advantage that only a single flushing station is to be provided and that the Detergent containers are not to be attached in the immediate vicinity of the SpUIstatlon but as compact tanks can be placed in a remote location. Usually used in cascade washes Required free-standing containers in which immersion rinsing takes place are not required here.

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In an advantageous development of the invention it is provided that essentially only that rinsing liquid is supplied to a detergent container from which washing liquid is removed in a previous washing cycle that drips from the object to be washed, while that washing liquid that drips the object has not taken when spraying, is returned in a known manner to the detergent container to which it has been removed.

In the case of spray-rinsing processes, it is generally known that the water that does not hit workpieces regain (SW-PS 353 927) by just that Water that hits workpieces and becomes contaminated in the process, collects in a drain funnel, while the water hitting the walls of the flushing container runs back into the same water tank and again is used, but in this known flushing method, only a single detergent container is in connection provided with the flushing station. The present embodiment of the invention, on the other hand, is based on the idea based on the distinction between rinsing liquid that has hit the object and rinsing liquid, which has been sprayed past the object, as part of a cascade connection in connection with to use several detergent containers with different concentrate carryovers.

The invention also relates to a multiple flush system with a flush station equipped with spray nozzles and a plurality of detergent containers, which are optionally connected to an inlet conduit and an outlet conduit of the Rinsing station can be connected.

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This multiple flush system is characterized in that a cycle control device is provided which connects a valve in the suction line of a detergent container with the inlet line of the flushing station and the return line of the flushing agent container connected to the inlet line in the previous cycle with the outlet line of the flushing station.

In an advantageous further development of this multiple flush system it is provided that in the suction lines of the detergent container controllable inlet valves and in the Arranged return lines controllable first return valves are, and that each one inlet valve eires detergent container with a first return valve another detergent dispenser is synchronized.

The control of the inlet valves and the return valves can take place via a program switching device which controls the timing of the individual flushing processes. If the time cycles for all detergent containers are the same are, each detergent container is supplied with substantially the same amount of washing liquid as it was taken during the previous clock cycle. Therefore, the liquidity levels remain in the individual detergent containers essentially constant.

This also applies to the carry-over of concentrate, so that continuous operation without intermittent Refilling is ensured over a longer period of time.

The first detergent container of the cascade, i.e. the one Detergent container, the rinsing liquid of which is intended for the last rinsing process, becomes clean Rinsing solution supplied via a separate inlet. This detergent container can be equipped with a level regulator

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be provided, which controls the inflow of the pure rinsing solution in such a way that the level of the rinsing agent oil tank always remains constant.

A particular advantage of this flushing system is that the spatial arrangement of the detergent container is not tied to the flushing station, but rather as a result of the synchronized control of the individual Inlet valves and return valves the desired allocation of flow and return independently of the spatial arrangement of the individual containers takes place.

In order to achieve a better use of detergent, you can switch between those amounts of detergent in the manner mentioned above a distinction is made between those that hit the object to be washed and those amounts of detergent which have been sprayed over. This can be done in advantageous development of the multiple flush system done in that underneath the object a collecting device is arranged for collecting the rinsing liquid that has dripped off the object, that the Aüaufleitung the collecting device on the first return valves with the return lines of the Detergent container is connected, and that a second drain line of the rinsing station via second return valves is connected to the detergent containers, the second return valve of each detergent container is controlled synchronously with the inlet valve of the same detergent container.

The inventive method and the multiple flush system is suitable for flushing all solid material parts, sheets, plate material, etc., ie parts, their

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Surface is accessible by spraying. The principle is also applicable to goods drums that have an internal spray device.

In the following an embodiment of the invention with reference to the single figure the drawing explained in more detail.

In the drawing, the object to be rinsed, which comes from an electroplating bath, for example, is denoted by 10. This object is hung or inserted into the rinsing station 11 in such a way that that he is from the rinsing liquid that comes from the spray nozzles 12 is sprayed, can be taken. The rinsing station 11 consists of a tub on which Side walls directed into the tub interior spray nozzles 12 are attached and in their bottom there are drainage openings, which will be explained later.

The lines 131 and 132 lead to the nozzles 12, form the branch lines of the inlet line 13. The feed line 13 contains a self-priming pump 14, via an inlet valve a to the first detergent container 15, via an inlet valve b to the second Detergent container 16, via an inlet valve c to the third detergent container 17 and via an inlet valve d is connected to the fourth detergent container l8. Of the inlet valves a, b, c, and d is only one is opened at a time, and the pump 14 is then flushing fluid from the detergent container in question sucked in and via the spray nozzles 12 against the item 10 is sprayed.

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4Λ

Above the bottom of the rinsing station 11 is a collecting device in the form of baffles 19 which are arranged so that they separate the sprayed rinsing liquid that drips from the object 10 from the rinsing liquid that runs off the walls of the rinsing station. The rinsing liquid dripping off the object passes through the first drain line 20 to the first return valves a ,, b ,, C ₁ , U ₁ , while the second return line 21 drains the rinsing liquid that has not hit the object. The second drain line 21 leads to the second return _{valves a 2} , b ₂ , Cp, dp.

In the first spray cycle a, the detergent is removed from the detergent container 15 and removed from the object to be rinsed 10, the concentrated residues of the treatment bath. The here of the Rinsing liquid that drips off passes through the first drain line 20 and the open return valve a. directly back into the concentrate bath 22 or it is first sent to a recycling plant 25 headed. This can, for example, consist of an ion exchanger, evaporator, ultra or normal filter, a reverse osmosis system and the like. From here, the prepared concentrate solution is transferred to the Concentrate bath 22 returned.

Spray solution which has not hit the object 10 and is therefore only moderately contaminated is returned to the same detergent container 15 from which it was removed _{during cycle a via the second drain line 21 and the opened valve a g.}

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During the rinsing cycle a, the valves a, a, and a _{2 are} open, while all the other valves are closed.

During the second wash cycle b, detergent is withdrawn from the second detergent container l6. the The solution dripping from the object passes through the first return line 20 through the now open Valve b, in the first detergent container 15, while that spray solution that the object 10 has not met, via the second drain line 21 and the open valve bp into the second detergent container l6 runs back.

During the third washing cycle, the washing liquid is withdrawn from the washing agent container 17 via the inlet valve c and sprayed against the object 10. The more heavily contaminated rinsing liquid is then passed through the first return line 20 and the valve C ₁ into the detergent container 16, while the less contaminated rinsing liquid runs back into the detergent container 17.

The last detergent container 18 is filled with pure rinsing solution, z. B. with fully desalinated water, the amount of which corresponds to the cascade system loss of the first Spray cycle corresponds.

Although in the present embodiment, four detergent containers I5 to L8 corresponding to four different Clocks are provided, the invention is of course not limited to this number. Depending on the application, both less and more detergent containers can be controlled in the manner described.

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The first return valves a, b, c, d., The second return _{valves a g} , b ₂ , C ₂ , d ₂ , and the inlet valves a, b, c and d are solenoid valves that are operated by a program control device (not shown) with the three valves marked with the same letter open at the same time.

In the refill line 24 of the last detergent container 18, a solenoid valve 26 is connected, which is controlled by a level measuring device 25, the level of the Container 18 measures, is controlled in such a way that the liquid level in the container l8 on a is kept constant. Pure flushing solution is introduced into the container 18 via the line 24.

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Claims (4)

Expectations Multiple rinsing process for surface wet treatment systems, in which the object to be rinsed in successive washing cycles from different detergent containers with washing liquids increasing less concentrate carry-over is sprayed and the draining rinsing liquid again in each case the container is directed, thereby marked, -that with each wash cycle at least a part of the draining wash liquid in a detergent container is supplied from which flushing fluid was removed in a previous flushing cycle. 2. Mehrfachspüiververfahren according to claim 1, characterized in that that essentially only that rinsing liquid is fed to a detergent container, from which rinsing liquid was removed from the object to be rinsed in a previous rinsing cycle drips off, while that rinsing liquid that did not hit the object during spraying in is returned in a known manner in the detergent container from which it was removed. 3. Mehrfachspülsystem with a equipped with spray nozzles rinse station and a plurality of detergent containers that are connected either to an inlet line and to a Außlaßleitung the winding station, characterized in that a Taktsteuereinrlohtung is vorgehsehen that, b at each clock, a valve (a, c, d ) connects in the suction line of a detergent container (15 to 18) with the inlet line of the rinsing station (2) and the return line of the detergent container connected to the inlet line in the previous cycle with the outlet line of the rinsing station. 909810/0367 4. M'.hrfachspülsystem according to claim 3, characterized in that that in the suction lines of the detergent container (15 to 18) controllable inlet valves (a, b, c, d) and controllable in the return lines C) first return valves (a ^ b ^ c ^ d,) are arranged, and that in each case an inlet valve (a, b, c, d) of a detergent container with a first return valve ( ^a l ' ^b l » ^c l' ^d l) ^another aid dispensers is synchronized. 5 · Multiple flushing system according to claim 2 or J>, characterized in that a collecting device (19) is arranged below the object (10) for collecting the rinsing liquid that has dripped off the object, that the drainage line (20) of the collecting device via the first return valves (a ₁ , b., C ,, d ₁ ) is connected to the return lines of the detergent container (15 to 18), and that a second drain line (21) of the rinsing station via second return valves (a ₂ , bp, c ₂ , d ₂ ) with the Detergent containers is connected, the second return valve {a. _{? t} h _{? J} c _{? J} <l _? ) of each detergent container is controlled synchronously with the inlet valve (a, b, c, d) of the same detergent container. 909810/0367